Quantum CNOT Gate with Actively Synchronized Photon Pairs

• URL: http://arxiv.org/abs/2505.03960v1
• Date: Tue, 06 May 2025 20:19:32 GMT
• Title: Quantum CNOT Gate with Actively Synchronized Photon Pairs
• Abstract summary: Controlling the synchronization of photons from probabilistic quantum sources plays a pivotal role in advancing efficient quantum information processing.<n>We report the realization of a probabilistic entangling gate operating on actively synchronized photon pairs, using a quantum memory based on warm atomic vapor.<n>We achieve a truth-table fidelity exceeding 85% and demonstrate Bell- inequality violation for all four Bell states.
• Score: 0.8796261172196743
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Controlling the synchronization of photons from probabilistic quantum sources plays a pivotal role in advancing efficient quantum information processing. We report the realization of a probabilistic entangling gate operating on actively synchronized photon pairs, using a quantum memory based on warm atomic vapor. We achieve a truth-table fidelity exceeding 85% and demonstrate Bell- inequality violation for all four Bell states. The reduction in visibility of the Hong-Ou-Mandel (HOM) interference introduced by the storage process is identified as a primary factor limiting the gate fidelity. We derive an exact quantitative relation between HOM visibility and gate fidelity for pure single photons, which applies to all photonic gates relying on interference, regardless of the physical platform.

Related papers

• Highly indistinguishable photons from a tin-vacancy spin qubit in diamond [0.0]
  Quantum networks promise secure communication, distributed sensing and modular quantum computing.<n>A key requirement is the indistinguishability of single photons, which directly impacts the fidelity of photonic operations.<n>Here, we demonstrate generation of highly indistinguishable single photons from a coherently excited tin-vacancy center in diamond.
  arXiv  Detail & Related papers  (2026-07-24T16:00:50Z)
• Integrated Photon-Memory Entanglement Generation using Dual Photonic Resonators [33.0739671779695]
  Integrated photonic architecture for telecom photon-memory entanglement generation based on dual silicon-carbide microring resonators.<n>We generate and verify photon-memory entanglement with a single-pair interference visibility of 88.1 $pm$ 10.6%.<n>Results establish the first integrated platform for photon-memory entanglement generation and provide a scalable route toward chip-scale quantum repeaters.
  arXiv  Detail & Related papers  (2026-07-01T18:00:02Z)
• High-fidelity entangled photon pairs from a quantum-dot-based single-photon source [2.2911874889696775]
  Entangled photon pairs are a ubiquitous resource in quantum technologies, used in quantum key distribution and quantum networking.<n>We demonstrate a high-fidelity source of "swappable" entangled photon pairs using a semiconductor quantum dot (QD) coupled to a tunable microcavity.<n>Our results establish semiconductor QDs as a viable platform for quantum network-compatible swappable entangled photon pair generation, with feasible entanglement generation rates exceeding 0.5 Gpairs/s.
  arXiv  Detail & Related papers  (2026-03-31T16:34:30Z)
• Deterministic Control of Photon-Number Probabilities via Phase-Controlled Quantum Interference [0.0]
  We report an all-linear-optical protocol that converts a single-photon emitter into a deterministic generator of vacuum--single-photon--two-photon states.<n>A fully quantum-mechanical, discrete time-bin model maps these results onto the tailored photon statistics.
  arXiv  Detail & Related papers  (2025-08-21T08:32:03Z)
• Entanglement Preservation and Clauser-Horne Nonlocality in Electromagnetically Induced Transparency Quantum Memories [0.0]
  Quantum memories are indispensable for quantum repeater networks, deterministic generation of single- or multi-photon states, and linear optical quantum computing.<n>This work bridges a long-standing theoretical gap and lays a solid foundation for the application of quantum memories in scalable quantum networks and quantum information processing.
  arXiv  Detail & Related papers  (2025-07-21T10:05:11Z)
• Scalable quantum interference in integrated lithium niobate nanophotonics [40.13294159814764]
  integrated lithium niobate is a prime contender for a monolithic quantum photonics platform.<n>We show bosonic interference between indistinguishable photons, a crucial interaction for many photonic quantum computing protocols.
  arXiv  Detail & Related papers  (2025-06-25T15:06:53Z)
• Optimizing the quantum interference between single photons and local oscillator with photon correlations [0.0]
  We report on two homodyne photon-correlation techniques enabling the precise measurement of the overlap between a single photon generated by a quantum dot-cavity device and pulsed laser light.<n>The different statistics of interfering fields lead to specific signatures of the quantum interference on the photon correlations at the output of the interfering beam splitter.<n>We compare the behavior of maximized overlap, measuring either the Hong-Ou-Mandel visibility between both outputs or the photon bunching at a single output.
  arXiv  Detail & Related papers  (2025-04-16T14:19:51Z)
• Quantum light sources with configurable lifetime leveraging parity-time symmetry [26.056219942960112]
  Device generates energy-time entangled photon pairs with 87.1 +- 1.1% interference visibility and a heralded second-order autocorrelation of g_h((2) ) (0)= 0.069 +- 0.001.<n>Our work highlights the potential of PT symmetry for advanced quantum applications, including high-speed communication and programmable quantum computing.
  arXiv  Detail & Related papers  (2025-04-02T07:04:31Z)
• Cavity-Quantum Electrodynamics with Moiré Flatband Photonic Crystals [35.119260614523256]
  A quantum dot can be tuned by a factor of 40, ranging from 42 ps to 1692 ps, which is attributed to strong Purcell enhancement and Purcell inhibition effects. Our findings pave the way for moir'e flatband cavity-enhanced quantum light sources, quantum optical switches, and quantum nodes for quantum internet applications.
  arXiv  Detail & Related papers  (2024-11-25T18:52:11Z)
• Entanglement of photonic modes from a continuously driven two-level system [34.50067763557076]
  We experimentally generate entangled photonic modes by continuously exciting a quantum emitter, a superconducting qubit, with a coherent drive.<n>We show that entanglement is generated between modes extracted from the two sidebands of the resonance fluorescence spectrum.<n>Our approach can be utilized to distribute entanglement at a high rate in various physical platforms.
  arXiv  Detail & Related papers  (2024-07-10T18:48:41Z)
• On-chip quantum interference between independent lithium niobate-on-insulator photon-pair sources [35.310629519009204]
  A lithium niobate-on-insulator (LNOI) integrated photonic circuit generates a two-photon path-entangled state, and a programmable interferometer for quantum interference. We generate entangled photons with $sim2.3times108$ pairs/s/mW brightness and perform quantum interference experiments on the chip with $96.8pm3.6%$ visibility. Our results provide a path towards large-scale integrated quantum photonics including efficient photon-pair generation and programmable circuits for applications such as boson sampling and quantum communications.
  arXiv  Detail & Related papers  (2024-04-12T10:24:43Z)
• Quantum interferences and gates with emitter-based coherent photon sources [0.0]
  In 2019, it was shown that the emitted single photon states often include coherence with the vacuum component. We show how such photon-number coherence alters quantum interference experiments. We illustrate the impact on quantum protocols by evidencing modifications in heralding efficiency and fidelity of two-qubit gates.
  arXiv  Detail & Related papers  (2024-01-02T12:29:49Z)
• Coherently driven quantum features using a linear optics-based polarization-basis control [0.0]
  Coherence approach has been applied to interpret quantum features such as the Hong-Ou-Mandel (HOM) effect. A perfectly coherent analysis shows the same photon bunching of the paired coherent photons on a beam splitter.
  arXiv  Detail & Related papers  (2023-03-22T15:09:14Z)
• Orbital angular momentum based intra- and inter- particle entangled states generated via a quantum dot source [0.0]
  This work employs a bright QD single-photon source to generate a complete set of quantum states for information processing with OAM photons. We first study the hybrid intra-particle entanglement between the OAM and the polarization degree of freedom of a single-photon. Then, we investigate the hybrid inter-particle entanglement, by exploiting a probabilistic two qudit OAM-based entangling gate.
  arXiv  Detail & Related papers  (2022-11-09T19:20:49Z)
• Hybrid quantum photonics based on artificial atoms placed inside one hole of a photonic crystal cavity [47.187609203210705]
  Hybrid quantum photonics with SiV$-$-containing nanodiamonds inside one hole of a one-dimensional, free-standing, Si$_3$N$_4$-based photonic crystal cavity is presented. The resulting photon flux is increased by more than a factor of 14 as compared to free-space. Results mark an important step to realize quantum network nodes based on hybrid quantum photonics with SiV$-$- center in nanodiamonds.
  arXiv  Detail & Related papers  (2020-12-21T17:22:25Z)
• Heralded non-destructive quantum entangling gate with single-photon sources [5.881327681338198]
  We demonstrate a heralded controlled-NOT (CNOT) operation between two single photons for the first time. Our results are an important step towards the development of photon-photon quantum logic gates.
  arXiv  Detail & Related papers  (2020-10-28T06:50:23Z)
• A bright and fast source of coherent single photons [46.25143811066789]
  A single photon source is a key enabling technology in device-independent quantum communication. We report a single photon source with an especially high system efficiency.
  arXiv  Detail & Related papers  (2020-07-24T17:08:46Z)
• Near-ideal spontaneous photon sources in silicon quantum photonics [55.41644538483948]
  Integrated photonics is a robust platform for quantum information processing. Sources of single photons that are highly indistinguishable and pure, that are either near-deterministic or heralded with high efficiency, have been elusive. Here, we demonstrate on-chip photon sources that simultaneously meet each of these requirements.
  arXiv  Detail & Related papers  (2020-05-19T16:46:44Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.